title: Molecular hydrogen formation from photocatalysis of methanol on TiO2(110).
abstract: It is well established that adding methanol to water could significantly enhance H2 production by TiO2. Recently, we have found that methanol can be photocatalytically dissociated on TiO2(110) at 400 nm via a stepwise mechanism. However, how molecular hydrogen can be formed from the photocatalyzed methanol/TiO2(110) surface is still not clear. In this work, we have investigated deuterium formation from photocatalysis of the fully deuterated methanol (CD3OD) on TiO2(110) at 400 nm using a temperature programmed desorption (TPD) technique. Photocatalytic dissociation products formaldehyde (CD2O) and D-atoms on BBO sites (via D2O TPD product) have been detected. In addition to D2O formation by heating the photocatalyzed methanol/TiO2(110) surface, we have also observed D2 product formation. D2 is clearly formed via thermal recombination of the D-atoms on the BBO sites from photocatalysis of methanol. Experimental results indicate that D2O formation is more important than D2 formation and that D2 formation is clearly affected by the D2O formation process.
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian 116023, Liaoning, PR China.
authors.forename: Chenbiao
authors.initials: C
authors.lastname: Xu
authors.forename: Wenshao
authors.initials: W
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Guo
authors.forename: Dongxu
authors.initials: D
authors.lastname: Dai
authors.forename: Maodu
authors.initials: M
authors.lastname: Chen
authors.forename: Xueming
authors.initials: X
authors.lastname: Yang
mesh_terms: D002384:Catalysis; D005557:Formaldehyde / Q000138:chemical synthesis* / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D055668:Photochemical Processes; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D005557:Formaldehyde; D006859:Hydrogen; D014025:Titanium; D000432:Methanol